After researching - I finally know what command is happening when I do the Command+V. However, this is not what I want, I just want to copy and paste. Why is everything I paste become a pasteblock?\

PASTEBLOCK:

As the command suggests it will paste copied object as a block in the current drawing. After pasting this drawing as a block you will find that AutoCAD will assign a completely random string of characters to its name which looks like A$605D409A but you can rename this block to something meaningful by using RENAME command.